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\section{TSP}
function ${TSP}(V, D)$\\
$\min _{e \in V, e \neq 1} M(V-\{e\}, e)+d_{e 1}$\\
function ${M}(S, e)$\\
1: if $S=\{v\}$ then\\
2: $\quad \mathrm{M}(S, e)=d_{1 v}+d_{v e}$\\
3: return $\mathrm{M}(S, e)$\\
4: end if\\
5: return $\min _{i \in S, i \neq e} \mathrm{M}(S-\{i\}, i)+d_{e i}$\\
$\sum_{k=2}^{n-1} k(k-1)\left(\begin{array}{c}n-1 \\ k\end{array}\right)+n-1=O\left(2^{n} n^{2}\right)$


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